1. Field of the Invention
This invention relates to a wrap for a large, lengthy outdoor tubular article, such as a cable of a suspension bridge or cable-stayed bridge, and to a method for applying such a wrap to such an article.
2. Description of the Prior Art
Cables for suspension bridges and cable-stayed bridges are exposed to severe outdoor climatic conditions and must be painted or otherwise coated to avoid rusting and other forms of deterioration that can result from such exposure. Traditionally, such cables were painted with weather-resistant paint, but periodic repainting of painted cables is still required, at substantial expense due to the relative inaccessibility of such cables, because of the severity of the climatic conditions to which such painted cables are often exposed. Removal of paint prior to repainting, which is often necessary for proper repainting, also raises environmental concerns.
More recently, it has become known that bridge. cables can be more permanently protected from exposure by spirally wrapping them with a strand of indefinite length of a Neoprene or similar polychloroprene material. However, a material of this type usually cannot be properly precolored to match or blend in appearance with the other elements of a bridge or other structure where it is to be used. Thus, it is customary, after spirally wrapping a bridge cable with a Neoprene covering, to paint the outer surface of the wrapping to thereby ensure a suitable color match between the cable and other bridge elements. This after painting step, of course, is quite labor intensive and therefore very expensive.
Further, in spirally wrapping a suspension bridge cable with a Neoprene covering, it is important that each turn of the covering be securely bonded to the preceding turn, to properly seal the seam therebetween and thereby prevent the ingress of moisture and dust into the interface between the covering and cable. In the use of Neoprene coverings of the type described, it was known that the seam could be sealed by providing a significant overlap between the successive turns of the covering and by bonding the overlapped layers to one another by the use of a solvent. However, the application of the solvent is also labor intensive, and therefore expensive, and many solvents are objectionable on environmental and health and safety grounds, therefore requiring great care in the handling and disposal of such materials. Further, the solvent sealing step tends to disturb a previously painted surface.